1. Field of the Invention
The invention relates to a door lock control device, and more particularly to a door lock control device that controls door locking and/or unlocking correspondingly to an input result into an input unit provided in a vehicle subject to the condition that a portable device is present within a detection area around the vehicle.
2. Description of the Related Art
A technology for controlling door locking/unlocking correspondingly to a detection result of a touch sensor provided in a vehicle subject to the condition that a portable device is present within detection area around the vehicle has heretofore been suggested. For example, Japanese Patent Application Publication No. 2006-9312 (JP-A-2006-9312) discloses a door lock control device in which a touch sensor for locking (described as “lock sensor”) and a touch sensor for unlocking (described as “unlock sensor”) are provided in the vicinity of a door handle. This door lock control device determines whether a portable device is present within the detection area. When the lock sensor detects the touch in a state in which the presence of the portable device is recognized, the door is locked, and when the unlock sensor detects the touch, the door lock is releases (the door is unlocked).
In the door lock control device described in JP-A-2006-9312 electric power is constantly supplied from a power source to the lock control sensor (general name of the lock sensor and unlock sensor) and, therefore, a large amount of power of the power source of the vehicle is consumed. Furthermore, because the power is constantly supplied to the lock control sensors, radiation is constantly emitted from the sensor circuit and this radiation can adversely affect other circuits or antenna.